Looking at finding a minidisc recorder can get confusing, with the huge number of model names and numbers. As time went on from the initial Sony MZ-1, the Sony naming convention changed and evolved. Then NetMD came along and shook it up a bit, and finally Hi-MD changed it again.
This page attempts to clarify the model naming conventions, starting with Sony Portables (the most widely sold and used, though there are other manufacturers).
To begin, the first few models began with MZ and a number; e.g. MZ-1 (full recorder), MZ-2P (playback-only).
For the second generation, the model names became a bit more uniform. They were differentiated by the third character in the model name: MZ-R2 being the first to use the new convention.
Going forward, the general idea was as follows (again, at least for Sony-produced models):
There were also subsets for some specific functionalities:
Finally, letters at the end of the model number had unique features:
Sony MD decks are in the MDS and MXD families. The MD-only decks are in the MDS series, while the MXD series are CD/MD dubbers.
* Sony LAM: desktop stereos with USB sound, NetMD, and CD→ MD dubbing * CMT and HCD: compact stereos/mini-compo stereos, CMT is usually the name of the bundle and HCD is the name of the individual system unit